TheEnterprisePC wrote on 2025-05-17, 10:54:Hello all! I'm new to the forum.
I recently got a Siemens Nixdorf PCD-4ND laptop. It's quite in a good condition despite of the […]
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Hello all! I'm new to the forum.
I recently got a Siemens Nixdorf PCD-4ND laptop. It's quite in a good condition despite of the screen - it's STN LCD with sign of aging. Yep it still work but I need this laptop to write something, and the nearly-aged STN screen makes me feel uncomfortable.
Thus I'd like to change it to a TFT one. Not sure whether there is one, or the one on TFT version of PCD-5ND may work. If so plz let me know the model.
Sincerely,
TheEnterprisePC
P.S. The STN screen on this laptop is Hitachi LMG9400XUCC. It has a connector of 29 pins (15+14).
It's probably best to find out more about the TFT version and work from there, this website has a few more details on the TFT version: https://adnoteh.ro/retrowikid/index.php/Sieme … Nixdorf_PCD-4ND
(unrelated but on that page, I really dislike that people keep rubbishing belt-driven floppy drives especially Citizen ones, they were actually quite fancy for their time making use of a brushless motor which was pretty new tech at the time, replacing a belt isn't that hard)
And Clous's site has some great pictures of what it's got inside: https://www.clous.cz/siemens-nixdorf-pcd-4nd-2/
This picture here shows that the LCD part is removable and uses a board-to-board connector:
The attachment Siemens-Nixdorf-PCD-4ND-TFT-18.jpg is no longer available
The mainboard has no markings or stickers on the BIOS chip to suggest that the mainboard itself is specific to the TFT model, that I can see. So I suspect that the LCD section installed decides whether the graphics chip operates in DSTN or TFT mode based on the LCD section connected.
The reason I mention this is that you probably can't switch your laptop manually to drive a TFT, it's decided by wiring on the board in the LCD section like a pin grounded here on the TFT version but not on the DSTN version and the laptop motherboard detects that at boot and sets the display mode accordingly.
The easiest way you can resolve it is to get the top half of a PCD-4ND that's got a TFT in it so that the graphics chip will drive it as a TFT.
Simply replacing the DSTN panel with a TFT in the existing housing won't work unless you do significant rewiring and figure out the switch that makes it drive a TFT display instead of DSTN.
